Politicians’ Prescriptions for Marijuana Defy Doctors and Data

New York Times—June 26, 2014

New York moved last week to join 22 states in legalizing medical marijuana for patients with a diverse array of debilitating ailments, encompassing epilepsy and cancer, Crohn’s disease and Parkinson’s. Yet there is no rigorous scientific evidence that marijuana effectively treats the symptoms of many of the illnesses for which states have authorized its use.

Instead, experts say, lawmakers and the authors of public referendums have acted largely on the basis of animal studies and heart-wrenching anecdotes. The results have sometimes confounded doctors and researchers.

The lists of conditions qualifying patients for marijuana treatment vary considerably from state to state. Like most others, New York’s includes cancer, H.I.V./AIDS and multiple sclerosis. Studies have shown that marijuana can relieve nausea, improve appetite and ease painful spasms in those patients.

The dearth of data has not prevented legislators and voters across the nation from endorsing marijuana for more than 40 conditions. Patients with rheumatoid arthritis, for instance, qualify for marijuana treatment in at least three states.

New York considered including the chronic inflammatory disease on its list, a development that astonished Dr. Mary K. Crow, an arthritis expert at the Hospital for Special Surgery, in Manhattan. People with rheumatoid arthritis have higher rates of certain respiratory problems, she noted.

“Inhaling into your lungs is not a great idea with rheumatoid arthritis, given the substantial number of patients who have lung disease,” Dr. Crow said. (The final version of New York’s law prohibits smoking marijuana and did not end up including rheumatoid arthritis.)